ABSTRACT: With growing recognition that community engaged research (CEnR) is a valid approach to examine and address social and health inequities, the U.S. has seen a proliferation of community-academic partnerships over the past decade. Community-based participatory research (CBPR), as one CEnR approach, emphasizes equitable partnerships between academic and community members to address pressing community health issues. An underlying assumption in these partnerships is that attention to appropriate processes, structures, and conditions will lead to success in long-term maintenance, achievement of goals, and improvement of health outcomes. However, despite this expectation for CBPR partnerships, little empirical evidence and few standardized measures exist to define the meaning of partnership success and the factors that contribute to success in long-standing CBPR partnerships. The purpose of this five-year study, in response to the National Institute of Nursing Research's (NINR) call for the creation of innovative measures for CEnR efforts, is to address this gap. Building upon the work of Israel and colleagues, and in collaboration with community and academic experts in CBPR, we will develop a clear definition of CBPR partnership success, develop a tool, ?Measurement Approaches to Partnership Success? (MAPS), that measures the intermediate and long-term factors that are associated with CBPR partnership success, test the tool with 55 long-standing CBPR partnerships across the U.S., develop feedback mechanisms for understanding the results of the tool, and disseminate the tool and feedback mechanism for broader use. Our specific aims are to: 1) clearly define CBPR partnership success and develop a tool (MAPS) to assess partnership success and its intermediate and long-term contributing factors in long-standing CBPR partnerships; 2) test the psychometric qualities of the MAPS tool in a sample of long-standing CBPR partnerships existing 6 years and longer; and 3) develop mechanisms to feed back and apply partnership evaluation findings, and widely disseminate the MAPS tool and feedback mechanism in a readily accessible and usable format.